Institution: | 1University of Manchester, Jodrell Bank Observatory, Macclesfield, Cheshire, SK11 9DL;2Columbia Astrophysics Laboratory, Columbia University, 550 West 120th Street, New York, NY 10027, USA;3NAIC, Arecibo Observatory, HC3 Box 53995, Arecibo, PR 00612, USA;4Australia Telescope National Facility, CSIRO, P.O. Box 76, Epping, NSW 1710, Australia;5Osservatorio Astronomico di Bologna, Via Ranzani 1, 40127 Bologna, Italy |